Third Assistant Engineer
Unlimited (Motor/Steam)
Third Assistant Engineer is the entry-level licensed engineer endorsement on the unlimited-horsepower ladder — the engine-room equivalent of Third Mate. Earned through a maritime academy or by upgrading from QMED with qualifying engine service and the full STCW engineer package.
Controlling regulation: 46 CFR 11.516
Where this fits in the ladder
Typically held first
Can lead to
Sea service
1,080
days required
Est. cost
$2,725–$4,800
training + docs + fees
Timeline
~4.3 yr
at full-time pace
Sea service requirement
Three years (1080 days) of engine-department service as a QMED, or completion of an approved academy/engineering program. Rating is set by plant type served on (motor, steam, or gas turbine).
Practical assessment: Officer in Charge of an Engineering Watch (OICEW) practical assessments.
Each day must be documented with a sea service letter showing vessel name, USCG Official Number, gross tonnage, route, position, dates, and total days served.
Track your sea service days free →STCW training required
Basic Safety Training
Personal survival, fire prevention, first aid, personal safety. Required for any mariner on an ocean or near coastal vessel.
Proficiency in Survival Craft
Launching lifeboats, rescue boats, and survival craft. Required for officers on STCW-regulated vessels.
Advanced Fire Fighting
Command and control of fire-fighting operations on vessels. Required for Master and officer-level endorsements 500 GT+.
Medical First Aid Provider
Medical emergencies, pharmacology, and practical care at sea. Required for officers on ocean vessels without a ship's doctor.
Written exam modules
Taken at a USCG Regional Exam Center. Practice each module free below.
Engineering Safety & General
Engine-room safety, pollution prevention, basic thermodynamics, and watchkeeping. 70% to pass.
Motor Plants (Diesel)
Diesel propulsion, fuel and lube systems, starting air, and troubleshooting. 70% to pass.
Steam Plants
Boilers, turbines, feedwater, and steam-cycle operation. Required for steam-rated endorsements. 70% to pass.
Electrical, Electronics & Refrigeration
Generators, distribution, motors, and refrigeration/AC plant. 70% to pass.
Application documents
TWIC Card
$125.25 · 5-year validity · TSA application + biometrics
Physical (CG-719K)
~$100–300 · Valid 12 months from exam date · Any licensed physician
Drug Test (CG-719P)
~$60–80 · Must be within 185 days of NMC receipt · SAMHSA-certified lab
Cost breakdown
Estimates only. Excludes optional exam-prep courses, travel, and lodging. Verify current NMC fees before applying.
How to apply at the NMC
The application path is the same for every credential — only the documents and exams above change.
- 1
Complete the application form (CG-719B)
Fill out the Application for Merchant Mariner Credential (CG-719B). Small-vessel operators may document time on the Small Vessel Sea Service Form (CG-719S). List every endorsement you are applying for.
- 2
Assemble your supporting documents
Gather your TWIC, CG-719K medical certificate (within 12 months), CG-719P drug test (within 185 days), sea service letters, course completion certificates, and a copy of any current MMC. Missing or stale documents are the #1 cause of delays.
- 3
Submit to the National Maritime Center
Send the package to the NMC by email, mail, or fax, or hand it to a Regional Exam Center. Pay the applicable evaluation, examination, and issuance user fees (46 CFR 10.219) via Pay.gov.
- 4
NMC evaluation
An evaluator reviews your file against 46 CFR. If anything is missing you receive an Awaiting Information (AI) letter; once complete you get an Approval to Test (ATT) letter, valid 12 months, listing the exam modules you must pass.
- 5
Take any required exams at a REC
Schedule your modules at a Regional Exam Center within the ATT window. Each module is graded separately — passes are banked, and you retest only the modules you miss.
- 6
Issuance
Once evaluation, exams, and the safety/security (TWIC) check are all cleared, the NMC prints and mails your MMC. A credential is valid for five years.
Forms and fees are set by the U.S. Coast Guard. Confirm the current CG-719 forms and NMC user fees at the National Maritime Center before submitting.
Build your Third Assistant Engineer plan
Track your credentials, log sea service days, and see exactly how close you are — free.